Helleborus purpurascens - Often the first flowers can be seen low to the ground in December (usually before the new foliage appears), but they continue to open as the red-spotted stems grow, right through until early spring. A variable but very pretty deciduous clump-forming perennial that makes excellent groundcover in partial shade.
Acanthus spinosus is an herbaceous perennial. There are other species but this is my favourite as I prefer it's more dissected, thistle-like leaves. A mature clump in flower is an impressive site. Scroll down this board for further details.
Zantedeschia aethiopica 'Crowborough' arum lily - Unusual, pure white hood-shaped flowers that are up to 10-15cm (4-6in) long are produced from late spring to mid-summer. It makes a striking architectural clump with lovely arrow-shaped, glossy dark green leaves. It looks great grown beside water as a marginal plant and can be left outside in most frost-prone areas if it is given a deep winter mulch.
Pettifers has a strong structure that makes it stunning in the winter. When the garden wakes up in late winter, it brings aconites and snowdrops, then hellebores. Shortly after, the meadow of snake’s-head fritillaries stretches out, followed by tulips // Great Gardens & Ideas //